Refrigeration



Aug. 15, 1939 P. STRANDBERG 2,169,320

7 REFRIGERATION Filed July 20, 1938 INVENT OR.

mfig/fui my ATTORNEY.

Patented Aug. 15, 1939 2,169,820 REFRIGERATION Paul Strandberg, Stockholm, Sweden, assignor, by mesne assignments, to Servel, Inc., New York, N. Y., a corporation of Delaware Application July 20, 1938, Serial No. 220,208

8 Claims.

My invention relatesto refrigeration obtained in connection with operation of internal combustion engines generally as described in Reissue Patent No. 19,350 to Carl Georg Munters and Sigurd Mattias Backstrom, and it is an object of the invention to provide in such a system an auxiliary evaporator for precooling of fluid flowing to a principal evaporator as more fully set forth in the following description and accompanying drawing of which the figure shows more or less schematically an internal combustion en-' gine and refrigeration system embodying the invention.

Referring to the drawing, an internal combustion engine I has an intake manifold II connectedby a conduit I2 toan auxiliary evaporator I3. The other end of evaporator I3 is connected by a conduit I4 to one passage I5 of a gas heat exchanger I5. The gas heat exchanger passage I5 is connected by a conduit 'II to one end of a principal evaporator I8. The evaporator I8 is provided with heat transfer fins and located in an insulated refrigerator compartment I9. The

other end of evaporator I8 is connected by a conduit 20 to a carburetor 2|. Liquid fuel is supplied to the carburetor 2I in known manner, not illustrated. The air inlet of carburetor 2I is connected by a conduit 22 to one end of the .other passage 23 of the gas heat exchanger I6. The other end of gas heat exchanger passage 23 is connected by a conduit 24 to an air inlet conduit 25 which extends centrally through the auxiliary evaporator I3 and has an open end 26 where atmospheric air or air from a cleaner enters.

An air inlet for evaporator I3 is provided at 21 by a conduit 28 in which there is a Venturi passage 29 or other suitable throttling device. Air inlet 21 is controlled by a valve 30. The gas heat exchanger I6 is slightly tilted from horizontal and the lower end of outer passage I5 is connected by a conduit3l to the throat of the throttling passage 29.

In operation, liquid fuel is supplied to the carburetor 2| in any suitable manner and air is drawn in at inlets 26 and 21., Air which enters the opening 26 flows through pipe 25, pipe 24, gas heatexchanger passage 23, pipe 22, and carburetor 2| to the evaporator I8. Liquid fuel is atomized into the air stream in carburetor 2I and atomized liquid fuel vaporizes and diffuses into air in evaporator I8 producing a cooling effect. Unevaporated liquid andthe mixture of air and fuel vapor flow from the evaporator through conduit IT to the outer passage I5 of gas heat exchanger I6. The air and vapor mixture then flows through conduit I4 to evaporator I3 and thence through pipe 62 and manifold II to the engine III.

Air which enters opening 21 flows through the throttle passage 29 into evaporator I3 and there joins the combustible mixture of fuel vapor and air flowing to the engine Ill in the previously described path. Unevaporated liquid flows "downward in the outer heat exchanger passage I5 and from the lower end of this passage flows through conduit 3| to the throat of the throttle passage 29 where it is atomized into the air and carried therewith into the evaporator'5 where it evaporates and diffuses into the air and vapor mixture producing a cooling effect for precooling of air flowing through the evaporator in conduit 25. Flow of liquid through conduit 3| is carried out by suction caused by pressure reduction at the throat of throttle passage 29. Air which enters opening 26 and then flows to the evaporator 29 as previously describedis precooled in evaporator I3 and heat exchanger I6. To increase the efliciency of the auxiliary evaporato'r I3, the auxiliary air supply at 21 may be drawn in heat exchange relation with cooled vapor and air mixture leaving the evaporator I3 through conduit I2 Va'riousother changes and modifications may be madewithin thescope of the invention which is not limited except as indicated in the following claims. What is claimed is: a 1. Refrigeration apparatus including an internal combustion engine, a plurality of places of evaporation, means for conducting air to one of said places of evaporation, means to conduct air to said second place of evaporation, means to con-'- duct liquid fuel to both of said places of evaporation, means to conduct vaporous fuel and air mixture from said first place of evaporation to said second place of evaporation and thence to said engine, said -first place of evaporation being arranged in heat transfer relation with'an object to be cooled, and said second place of evaporation being arranged in thermal exchange relation with air. flowing to said first place of evaporation.

2. Apparatus as set forth in claim 1 in which unevaporated liquid fuel is conducted from said first place of evaporation to said second place of evaporation. I

3. Apparatus as set forth in claim 1 in which liquid fuel is syphoned to said second place of evaporation by fiow of air to said second place.

' in another of said places of evaporation by conduction from air flowing to said first place of evaporation, flowing vaporous fuel and air mixture from said first place of evaporation to said sec 0nd place of evaporation and thence to said engine.

6. A method of refrigeration as set forth in claim 5 in which unevaporated liquid fuel is conducted from said first place of evaporation to said second place of evaporation.

'7. A method of refrigeration as set forth in claim 5 in which liquid fuel is syphoned to said second place of evaporation by flow of air to said second place.

8. A method of refrigeration as set forth in claim 5 in which heat is exchanged between air flowing to said first place of evaporation and vaporous fuel and air mixture flowing from said first place of evaporation towards said second place of evaporation.

PAUL S'I'RANDBERG. 

